1. Permutation entropy: A natural complexity measure for time series;Bandt;Phys. Rev. Lett.,2002
2. Entropy of interval maps via permutations;Bandt;Nonlinearity,2002
3. Ordinal symbolic dynamics;Keller,2005
4. D. Knuth, The art of computer programming. Volume 3: Sorting and searching, Addison-Wesley, Reading, MA, 1973.
5. Group representations in probability and statistics;Diaconis,1988